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Hello l would like to know has anyone here pushed rb26 rods passed 400RWKW mark and beyond and how long they have lasted? The reason l ask this, is my friend just picked up a TO4z kit for a steel and although he has a built bootom end with supporting mods with the exception of the standard rods he would like to know how far he can safley push it in its current form?

thanks.

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more power = more load on rods, eg a 250kw rb26 would probably live past 9000rpm with stock rods.

500kw and 9000rpm and I would expect them to snap like twigs

but 500kws and 6000rpm it would last a whole lot better

Yep both torque and revs put load on the rods.

However if you rev it to 10k with even stock power there's a reasonable chance of it letting go, as revs increase the force goes up exponentially, the torques effect on load on the rod is linear.

I think if you keep the revs low enough you could probably get away with some absolutely incredible torque levels before breaking them, you would almost certainly break everything else first.

Interesting read about here and here

http://www.f1technical.net/forum/viewtopic.php?f=4&t=7039

http://www.motoiq.com/forum/aff/10/aft/17/afv/topic.aspx

basically, the answer to how strong are they ? it is complicated and depends on lots of things.

Edited by Rolls

Thanks to everybody who replied. From what l have can understand rb 26 rods can punch well above there weight depending on how it is tuned and staying below 9000rpm. Its a shame when the motor was built they didn't use aftermarket rods as it has everything else to support big power.l guess it all comes down to what you can afford at the time.

Thanks to everybody who replied. From what l have can understand rb 26 rods can punch well above there weight depending on how it is tuned and staying below 9000rpm. Its a shame when the motor was built they didn't use aftermarket rods as it has everything else to support big power.l guess it all comes down to what you can afford at the time.

You can make ridiculous power by staying under 9000rpm. Chances are it would get blown up by detonation from tuning or some sort of oiling problem before a rod let go. In fact has anyone ever seen a 26 fail due to the rods... ever?

Edited by Rolls

ye..Plenty of 800-1000hp RB26s make their peak power at 8200-8500, and realisticly the heads just arent designed to flow decent amounts of air past that

Edit - to answer your edit, yeah Ive seen a few bent ones over the years, from over revs/det etc...at 400+ they will be the first thing to fail with even the slightest hint of det or an over rev

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